<Try to describe precise steps that lead to the problem (where do you click, what keys do you press, what do you see, etc.)>
<If relevant, consider attaching a session log file or a screenshot)>

WinSCP 5.21.7

Error message:
Ошибка доступа к памяти.

Трассировка стека:
(0043D33F) System::DoneExcept
(00057016) ntdll.dll
(0000F15E) ntdll.dll.KiUserExceptionDispatcher
(003C9C40) System::Classes::_18201
(00015307) USER32.dll
(00015D45) USER32.dll
(000167D2) USER32.dll
(00016895) USER32.dll.DispatchMessageW

(0043CF2C) System::HandleAnyException
(00057016) ntdll.dll
(0000F15E) ntdll.dll.KiUserExceptionDispatcher
(003C9C40) System::Classes::_18201
(00015307) USER32.dll
(00015D45) USER32.dll
(000167D2) USER32.dll
(00016895) USER32.dll.DispatchMessageW

Status: all_insignificant

The problem happens rarely. I cannot reproduce it.